The present invention relates to a connecting rod made of composite material, especially for--internal-combustion engines, as well as to a method for manufacturing such a connecting rod.
Such a connecting rod is an elongate component which includes, in addition to a central shank, a wider big end, which is the part of the connecting rod lying on the crankshaft side, and a narrower small end, which is the part of the connecting rod lying on the piston side. In order to mount it, the big end must be able to open, and it therefore includes two elements fastened by two bolts which exert a significant stress on that surface of the element against which they are tightened. The connecting rod is a component which has a preferential direction of loading and has to have a high stiffness preventing deformations around the bores of the small end and the big end.
A connecting rod made of composite material is already known, for example from Patent FR-A-2,654,483. By composite material is meant a material which includes a reinforcement of yarns or fibers, this reinforcement being embedded in a matrix of cured synthetic material. Such a composite material, in addition to the weight saving that it provides, withstands mechanical loads extremely well, has a high corrosion resistance and excellent high-temperature behavior. However, in Patent FR-A-2,654,483, these properties of composite materials are not fully exploited on account of the fact that, in this case, the shank, small end and big end of the connecting rod are produced in the form of separate components connected by adhesive bonding and winding of a yarn, forming a strap. Furthermore, such a production is complicated and has to be implemented in several steps, thereby preventing effective mass production of such connecting rods.